Grants for Eliminating the Toxic Hazard of Environmental Lead in Our Towns Act of 2021 or GET THE LEAD OUT Act of 2021 This bill addresses lead-based hazards in housing. It also modifies the tax treatment of carried interest, which is compensation that is typically received by a partner of a private equity or hedge fund and is based on a share of the fund's profits, and the estate tax. The bill modifies the tax treatment of carried interest by requiring it to be included in gross income and taxed as ordinary income, with certain exceptions. Under current law, carried interest is taxed as investment income. In addition, the bill reduces the estate tax exemption amount from $10 million to $5 million. With respect to lead-based hazards, the bill allows the Department of Housing and Urban Development (HUD) to provide grants to state and local governments to reduce lead-based pipe hazards in housing. Additionally, HUD must require risk assessments, inspections, interim controls, and abatement of these hazards in federally assisted housing. HUD and the Environmental Protection Agency (EPA) must require the disclosure of such hazards in housing that is for sale or lease. Persons that fail to disclose such hazards are subject to civil penalties from HUD and may be liable to purchasers or lessees for damages. Additionally, the EPA must ensure that individuals who work with lead-based pipes have proper training and certification. States may enforce and administer such training and certification programs upon receiving EPA approval.